Tuberculosis is an opportunistic infection in individuals with HIV-AIDS that is estimated to infect 30% of the world's population. There are 8.8 million new cases every year and 10% of Mycobacterium tuberculosis infected individuals will develop active infections. The World Health Organization estimates that two million people die every year from tuberculosis.
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, is a gram-positive bacillus that is a nocardioform actinomycete. Because Mtb is slow growing and evades the host immune system, the human host becomes a reservoir of the mycobacteria. Each individual with an active Mtb infection infects on average 10 to 15 more individuals. Of these infected individuals, 3-4% will develop active disease immediately, and 5-10% will develop active tuberculosis within their lifetime.
HIV infection predisposes individuals to active infection with Mtb. It is estimated that 10% of HIV positive individuals are also Mtb infected. HIV-positive individuals are much more susceptible to developing active disease and approximately 13% of AIDS deaths worldwide are due to Mtb.
Current treatment regimens require the use of multiple antibiotics over a two month period utilizing isoniazid, rifampicin, pyrazinamide and ethambutol or streptomycin, followed by another four months of treatment with isoniazid and rifampicin. The difficulty in complying with this regimen has led to bacterial resistance to front-line TB drugs rifampicin and isoniazid. Drug resistance is leading to an increased TB burden in the population.
Accordingly, new approaches are required to combat the emergence of virulent multi-drug resistant organism (MDR-TB), which are defined as simultaneously resistant to both isoniazid and rifampicin, and extensive drug-resistant organism (XDR-TB), which are defined as MDR-TB that have simultaneous resistance to three or more of the six major classes of second-line drugs. The major classes of second line drugs include aminoglycosides, polypeptides, fluoroquinolones, thioamides, cycloserine, and para-aminosalicylic acid. These new approaches to treating an AIDS-related opportunistic infection should be effective against both sensitive and drug-resistant strains of M. tuberculosis. 
Additionally, the incidence of non-tuberculosis mycobacterium infections is increasing at an alarming rate among people with HIV-AIDS. New approaches are needed to treat these infections and diseases caused by mycobacterium.
Approaches to treating mycobacterium may also be used to target other infectious Actinomycetes. For instance, Nocardia sp. have genomes similar to that of Mycobacterium sp and may benefit from approaches used to treat mycobacterium.
Substituted 6-azaandrostenones were developed by scientists at Glaxo Smith Kline for use as 5α-testosterone reductase inhibitors. These compounds were described and patented in U.S. Pat. No. 5,708,001 to Andrews, et al.